Modulating device and muffler for pneumatic piano-players.



M. CLARK.

MODULATING DEVICE AND MUFFLER FOR PNEUMATIC PIANO PLAYERS.

APPLICATION FILED APR. 15, 1914.

1,136,656. Patented Apr. 20, 1915.

5, has communication with the atmosphere UNITED STATES PATENT OFFICE.

MELVILLE CLARK, OF CHICAGO, ILLINOIS, ASSIGNOR TO MELVILLE CLARK PIANO COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MODULATING DEVICE AND MUFFLER FOR PNEUMATIC PIANO-PLAYERS.

Specification of Letters Patent.

Patented Apr. 20, 1915.

Application filed April 15, 1914. Serial No. 831,903.

To all whom it may concern Be it known that I, MELVILLE CLARK, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Modulating Devices and Mufliers for Pneumatic Piano-Players, of which the following is a specification, reference being had to the accompanying drawin s, forming a part thereof.

he purpose of this invention isto provide an improved device for'modulating the action of an auto-pneumatic piano player, particularly adapted for the purpose of modulating the loudness of the playing when the exhaust is produced by a motor device which operates. continuously at a substantially uniform rate adequate for producing the maximum exhaust tension desired.

It consists in the elements and features of construction shown and described as indicated in the claims. I

In the drawings: Figure 1 is a plan view of a portion of the exhaust action of a piano player embodying this invention. Fig. 2 is a section at the line, 2, 2, on Fig. 1. Fig. 3 is a section at the line, 3, 3, on Fig. 2. Fig. 4 is section at the line l4 on Fig. 2 showing a detail plan view of one of the muffler diaphragms. Fig. 5 is section at the line 55 on Fig. 2 showing a plan view of a certain valve and valve seat more particularly hereinafter described.

In the drawings there is shown a portion, 1, of a main air trunk which may be understood as connected with an exhaust device, not shown, and with an exhaust chamber or reservoir, not shown, for producing the necessary condition of partial vacuum in' the chambers and passages of the pneumatic .action of the piano player.

The device which constitutes this invention comprises a two-part air chamber, 2, of which the one part, 3, is connected by a tube, 4, with the trunk, 1, and the other part,

through ports, 6, hereinafter more particularly described and controlled, as herein-- after described. The two chambers, 3 and 5, communicate through the partition wall or diaphragm, 7, the port of communication, 8, being controlled by a slide valve, 9, operated by a stem, 10, which extends out through a properly packed bearing, 11, at one end of the chamber, 5. The port, 8, is

.so that all the ports may be open to their full extent at one time. 'The width or diameter of the ports, 13, are all quite narrow in the direction of the slide valve, relatively to the sum of said dimensions or width transversely to said movement of all the ports in each row, so that each row in the wall of the chamber, 5, and in the valve, 12, constitutes the equivalent of a narrow transverse slit therein. The purpose of this construction is that a "cry slight movement of the valve may completely open or completely close all the ports, producing a quick opening and quick closing valve structure.

So far as described, the operation 016' the device is that when the exhaust device pumper or motor, not shown, is operating at its maximum if the valve, 9, is fully closed, the full force of the motor or pumper will be operative to produce a relatively high vacuum exhaust tension in the chambers and passages of the player action, and when it is desired to diminish this tension for softening the'tone, the valve, 9, being opened more or less, will affect such softening more or less by relieving the tension to the extent that air is admitted through the port, 8. .In order to be thus freely admitted the atmospheric communication of the champlaying with the loudness determined by such adjustment of the valve, 9, it is desired to accent any particular note or succession of notes by striking them wlth the full force which can be produced by the unrelieved action of the exhaust devices, this may be done by closing the valve, 13, shutting oil the atmospheric communication. Since this valve can be closed and opened completely by a very short movement, it serves to produce the effect of accenting or striking loudly a single note, however short, and returning immediately to the degree of loudness for which the valve, 9, is set, thus playing with any predetermined loudness, the

operator may by means of devices readily the valve, 12, opposed between it and the atmosphere. This muiiler device consists of a plurality of felt diaphragms, 16, 16, two bein shown and any member being permissible, each having a multiplicity of apertures, 16, the apertures of the successive diaphragms being staggered with respect to each. other so that there shall not be a directair path through the entire series at any point.v These felt diaphragms having an outer cover, 17 having a large or free air inlet, 17, are assembled upon the outer wall of the chamber, 2, alternatingwith spacing frames, 18, 18, 18, the frame 18, being mounted directly upon the side of the chamber, 2, encompassing the valve, 12, so

7 that there is formed substantially a chamber or hood about the valve, .12, which is divided by the felt diaphragms, 16, into as many compartments as the number of said felt diaphragms plus one, through all of which the air must pass to enter the chamber, 5, and in passing which it will be so broken up as to be prevented from any appreciably audible sound. The valve, 12, is operated by a stem, 20, which extends out throughthe end of the spacing skeleton, 18.v This valve is preferably made, as to its body or main portion, of felt, being mounted upon a bar, 12, for holding itlongitudinally in shape and operating and guiding it, its guidance and holding to its seat being effected in the customary manner by headed guide studs, 21-, extending through suitably elongated apertures in the valve and the bar, 12 and having springs, 22, interposed between the head of the studs and the bar, 12. Iclaim: I

1. In a piano player exhaust mechanism, in combination with an exhaust air trunk, :1

relief device comprising a two-part air chamber having one part connected with the trunk and the other part with the atmosphere; a valve which controls communication between the two parts having relatively long travel for progressive opening and closing, and a valve which controls communication of the second part with the atmosphere having a short movement for full opening and closing.

2. In a piano player exhaustmechanisin, in combination with an exhaust air trunk, a two-part air chamber, a gradually-opening valve controlling communication between the two parts of thechamber having relatively long travel for progressive opening and closing, one part having free air connection with the air trunk, and the other part having an apertured wall; an apertured and longitudinally slidable valve seating on'said wall, the apertures of the valve and wall being adaptedto register at one position of the valve, and being each narrow in direction of the valve-sliding movement, whereby the valve is adapted for quick opening and closing. a

3. In apianoplayer exhaust mechanism, in combination with an exhaust air trunk, a two-part air chamber, a gradually-opening valve controlling communication between the two parts of the chamber, having relatively long travel for progressive opening and closing, one part having free air communication with the air trunk, the other part having an exterionwall apertured for atmos pheric communication; an apertured and longitudinally-sliding valve seating on said wall, the apertures of the valve and wall being adapted to register respectively at one position of the valve, said apertures in the valve and wall being arranged in rows transversely of the sliding movement ofcthe valve, and having their diameter or width in the direction of the sliding movement small relatively to the aggregate dimension transversely of the direction of said sliding movement of all the apertures in each row.

4. In an' piano player exhaust mechanism, in combination with an exhaust air trunk, a relief device comprising a two-part air chamber having one part connected with the trunk and the other part communicating with the atmosphere; a valve-which con- -trols communication between the two said parts and a'inufller device consisting of a hood'seated on the air chamber-encompassing the atmosphere communication'thereof and having its atmosphere-intake-mouth remote from said seat and comprisingintermediate said mouth and seat a plurality'of diaphragms spaced'apart and having each 'amultiplicity of relatively small apertures for breaking up the current of air entering through said atmosphere-intake mouth.

5. In a'piano player exhaust mechanism" a izoalw a relief device comprisin a chamber having atmosphere inlets and a 00d encompassing such inlets having an atmosphere-intake mouth remote from said inlets and intermediate between said mouth and said atmosphere inlets, a plurality of diaphragms spaced apart, each having-a multiplicity of relatively small air apertures.

,6. In a piano player exhaust mechanism, a relief device comprising a chamber having atmosphere inlets and a hood encompassing atmosphere inlets and a hood encompassing such inlets having an atmosphereintake mouth remote from said inlets and having intermediate between said mouth and said atmosphere inlets a plurality of diaphragms spaced apart and having each a multiplicity of apertures, said apertures of each diaphragm being staggered relatively to those of the adjacent diaphragm for preventing the air from taking a direct path. I

In testimony whereof, I have hereunto set. my hand at Chicago, Illinois,'this 10th day of April, 1914.

I MELVILLE CLARK. Witnesses:

'CHAs. S. BURTON,

I LUCY I. STONE. 

